Ryan chipped the ball to Josh Kennedy outside 50m before sprinting to the goalsquare.

By the time Kennedy launched his long bomb, Ryan was in place to leap on top of Melbourne ruckman Max Gawn to take the spectacular mark.

The ensuing goal gave West Coast an important edge.

"That was a spectacular mark, we'll take that. But the work he's doing off the ball is really pleasing as well," Eagles coach Adam Simpson said. "He runs like a 24, 25-year-old mature age high half-forward.

"He's learning from one of the comp's better high half forward in Jamie Cripps in how he runs. And he's bought in."

When Jamie Cripps nailed a running goal from 55m out with six minutes remaining, the lead was 12 points and Melbourne were in big trouble.

The result was put beyond doubt when Jack Darling toed the sealer from point-blank range after Melbourne defender Sam Frost fumbled a ball on the goal line in embarrassing fashion.

The 13.7 (85) to 9.15 (69) win improves West Coast's record to 6-3.

But veteran Lewis Jetta faces a nervous wait after pinning the arms of Tim Smith and slamming his head into the turf in a strong tackle.

Melbourne are struggling at 3-6, but can be heartened by their best performance of the season.

"It was a young group that travelled to Perth and showed a lot of fight and a lot of resilience and played in the right way," Demons coach Simon Goodwin said.

The Demons won the inside 50m count 62-47, contested possessions 158-141, and the clearances 39-33.